End plug for rolled materials

ABSTRACT

A new concept of end plugs which are circular, concentric and symmetrical containing flanges at particular angles in front and back to produce a mechanical strength, is disclosed.

This application is a continuation in part of application Ser. No.465,762, filed May 1, 1974 by Henry L. Mason and now abandoned.

This invention relates to an improved end plug for shipping reels ofmaterial, or rolls of material, such as tape, paper rolls, or rolls ofplastic sheets. The new end plug design is such that the end plug isvastly superior in strength to any end plug heretofore used. In fact,the end plug will no longer be the weakest point in the packaging, beingstronger than the end plate of a typical packaging product.

It is known in the art that an end plug, which is not an integral partof the end plate of the package for rolls of material, is the typicalpackage concept for heavy rolls of sheet goods. Heretofore, numerousdesigns have been set forth for end plugs including those found in U.S.Pat. Nos. 3,353,660 to G. H. Wills issued Nov. 21, 1967; 2,269,939 toJanisch issued Jan. 13, 1942; 1,487,633 to F. G. Washburn issued Mar.18, 1924; and 3,710,539 issued to Cothran and Kirk Jan. 16, 1973; and,in addition, 3,083,928 issued to M. C. Voissem on Dec. 2, 1963. Aninspection of these patents will show numerous designs of what is knownin the industry as end plugs, some with fluted edges, some with multipleinternal ribbings, and some of metal to be driven within the rollitself. However, other than the metal end plug which is used in adifferent art with a wooden roll, these end plugs have been found to beweak and fail in the flexion mode due to the end plug deforming into anon-circular shape causing the rolls of paper, sheet goods, film or tapeto be dropped and damaged upon impact within the shipping container.Therefore, it has long been felt that an end plug which would not besubject to this type of failure in normal service would serve a neededpurpose in the art.

It is an object of this invention to supply an end plug, simple indesign, which will not, under normal use and with a normal roll of sheetgoods whether paper, plastic, film or tape, fail in the flexure andcompression mode.

It is another object of this invention to supply end plugs which are ofa simple shape and yet structurally twice as strong, as any designheretofore known.

Other objects of this invention will become clear to those skilled inthe art by reading the following description of the invention.

If one will refer to the FIGS. 1-12, which illustrate six conceptswithin this invention, one will note that FIGS. 1 and 2; 3 and 4; 5 and6; 7 and 8; 9 and 10; and 11 and 12 are paired side sectional views andfront views of six distinct examples of the end plug of this invention.

FIG. 2 is a front view of an end plug showing the circular, concentric,and symmetrical design of the plug. FIG. 1 is a section through thediameter of the end plug shown in FIG. 2, distinctly showing therelationship between the second flange, sleeve, and back flange of theend plug.

FIG. 3 is a similar section of the end plug shown in front view in FIG.4 where the front flange contains two slopes with respect to the sleeve.

FIG. 5 is a similar section of the end plug shown in front view of FIG.6 where an inner sleeve is added.

FIG. 7 is a sectional view of the end plug shown in the second view inFIG. 8 and combines an inner sleeve and a second flange of two slopes.

FIG. 9 is a second view of an end plug shown in cross section in FIG.10. This end plug depicts the lack of taper of the sleeve for a distanceH beyond the back flange.

FIGS. 11 and 12 show an end plug of the invention where the secondflange has been recessed within the sleeve.

More particularly, it has been found that where the sleeve, item 2, ofthe end plug, item 1, is perpendicular to the continuous back flange,item 3, and the continuous second flange, item 4, that an end plug isachieved with considerable strength in flexion. This is the equivalentof ribbing running concentric to the sleeve resulting in the increasedstrength observed.

It has been found that where an end plug is used to carry a "standard"roll of polyester film, the sleeve should usually be no less than oneinch long from the base of the back flange to the top of the secondflange and usually no longer than six inches, dimension X in FIG. 1. Thepreferred embodiment for standard end plugs wherein the diameter,dimension Y in FIG. 2, is approximtely 5 to 7 inches, is to have thesleeve length, X, within a 2 to 7 inch range. Naturally, this distancecan be maintained by recessing the front flange so that it is a smallerdistance from the back flange than the length of the sleeve. Thus inFIGS. 11 and 12, the distance from the top of the back flange to the endof the sleeve X is greater than P, the distance from the top of the backflange to the top of the front flange. P is never greater than 6 inches,whereas X may be 7 inches or longer. The recessed second flange is apreferred embodiment since it allows one to have a long sleeve for easeof roll mounting, but retains the second flange near the stress area ofthe end plug for the needed strength. That is, the stress points of theend plug occurs near the back flange which engages the packagingcontainer. The preferred P distance is between 1 and 4 inches.

Naturally, X will, to a great extent, vary in proportional relationshipto Y, the diameter of the plug, depending upon the depth of insertioninto the roll to result in a stable package. Thus, in a small plug wherethe Y dimension is only 21/2 inches, the sleeve dimension X willpreferably be in a range of 1/2 to 5 inches; however, the X dimensionmay be greater than 5 inches if package stability requires it.

As indicated above, in order to achieve the proper structural andflexural strength, it is imperative that a continuous back flange whichis perpendicular, 90° plus or minus 10°, to the sleeve be provided andthat, in addition to a second flange, wherein at least a portion of saidflange is nearly perpendicular, that is at an angle of between 80° and100°, to the sleeve is provided. This configuration has been found toadd rigidity to the end plugs, thus allowing even distribution acrossthe end plug sleeve of the downward force of the roll being stored uponthe end plug. The second and rear flanges, although rather light intotal weight add sufficient structural strength to enable thisconfiguration to exceed the strength of the normal side boards used in apackaging container for film or paper, and the strength of standard endplugs.

In addition to adding structural strength, the back flange, item 3, alsoaids in maintaining the horizontal stability of the packingconfiguration, since it does not allow the end plugs to pass through theside board of the packaging container and keeps the roll in a properposition within the packing container.

Referring now to FIG. 3, the basic design and concept of structuralstrength is provided; however, one additional angle is added by havingthe front flange at an angle less than 90° prior to becomingperpendicular to the sleeve. The first angle of the front flange in thisconfiguration is no less than 15° and no greater than 75° to have addedstructural strength. However, any combination of angles, so long as thesecond flange has a good portion of its overall width, 20% or more itsarea, perpendicular to the sleeve is contemplated. Preferably at least40% of the area of the second flange is perpendicular to the sleeve.These angular relationships for the second flange hold even if therecessed design of FIGS. 11 and 12 is used.

Referring to FIGS. 5 and 7, cross-sections of two additional examples ofend plugs of this invention, an additional item is added for morestrength, item 5. Item 5, called an inner sleeve, is a third surfaceperpendicular to the second flange and parallel to the sleeve. Thisinner sleeve gives added strength.

In a preferred embodiment of this invention, the intersection of thesurface of the sleeve and the back flange, intersection L, or thesleeve, with the second flange in non-recessed end plugs, intersectionM, is rounded into a convex or concave radius. The use of a radiusinstead of the surfaces meeting at a sharp angle will further enhancethe strength of the end plug. This invention contemplates the mold forthe end plug being built to introduce a rounded surface intersection.Although the radius of the surface intersection is not critical, itusually will be less than 1/4 inch. It is contemplated that theintersection of the second flange and the inner sleeve, intersection N,will also be rounded in accordance with the above description.

Finally, it has been found that end plugs of the greatest strengthwithin the invention of the application, are achieved where thethickness of the sleeve, as shown in FIG. 10, is increased by keepingthe outer surface of the sleeve exactly perpendicular to the backflange, whereas the inner surface follows the small taper associatedwith injection-molded pieces, that is, it is at an angle of at most 10°off the perpendicular. This thickened portion is only H dimension long,usually 1/10 to 1/2 of the sleeve length X. The preferred end plug ofthis invention would have said thickened sleeve as shown in FIG. 10 and,in addition, the recessed second flange as shown in FIG. 12.

Having thus described my invention, I claim:
 1. An improved end plug fora rolled goods packaging container which comprises a .[.circularcylinder known as a.]. .Iadd.cylindrical .Iaddend.sleeve having anexternal surface upon which the rolled goods are placed and an internalsurface, .[.which is.]. .Iadd.said sleeve being .Iaddend.concentric toand around a symmetrical axis with a continuous back flange, said backflange being nearly perpendicular to the sleeve.[.;.]. .Iadd.,.Iaddend.the outer diameter of said back flange .[.is.]. .Iadd.being.Iaddend.greater than the sleeve, and a second flange attachedcontinuously to the sleeve .[.at.]. .Iadd.and recessed therein inwardlya distance from .Iaddend.the front of said sleeve, said second flangebeing concentric to and symmetrical with said sleeve and at least 20% ofthe area of said second flange being perpendicular to said sleeve,.Iadd.a first portion of the external surface of .Iaddend.said sleevebeing at an angle of 90° to the back flange for a distance.Iadd.extending from said back flange of said sleeve .Iaddend.of up toone-half of the sleeve length and .[.then.]. .Iadd.the remainder portionof said sleeve external surface .Iaddend.tapers .[.at an angle of up to10% off the vertical.]. .Iadd.with a taper of up to 10° inwardly towardsaid symmetrical axis .Iaddend.and the internal surface .Iadd.of saidsleeve .Iaddend.tapers .[.at an angle of up to 10° off the vertical withrespect to the back flange in the direction of the symmetrical axis.]..Iadd.with a taper of up to 10° inwardly toward said symmetrical axisand from said back flange in the direction of said secondflange.Iaddend.. .[.2. An end plug according to claim 1, wherein thesecond flange is recessed within the sleeve..].
 3. An end plug for arolled goods packaging container which comprises a .[.circular cylinderknown as a.]. .Iadd.cylindrical .Iaddend.sleeve having an externalsurface upon which the rolled goods are placed and an internal surface,.[.which is.]. .Iadd.said sleeve being .Iaddend.concentric to and arounda symmetrical axis with a continuous back flange, said back flange beingnearly perpendicular to the sleeve.[.;.]. .Iadd., .Iaddend.the outerdiameter of said back flange .[.is.]. .Iadd.being .Iaddend.greater thanthe sleeve, and a second flange attached continuously to the sleeve.[.at.]. .Iadd.and recessed therein inwardly a distance from.Iaddend.the front of said sleeve, said second flange being concentricto and symmetrical with said sleeve and at least 20% of the area of thesaid second flange being perpendicular to said sleeve, and in additionan inner sleeve parallel to said .Iadd.first .Iaddend.sleeve andperpendicular to said second flange .Iadd.and .Iaddend.attachedcontinually to said second flange at the point of intersection .[.to.]..Iadd.of .Iaddend.said second flange and inner sleeve.
 4. An end plug inaccordance with claim 1 wherein the entire area of said second flange isperpendicular to said sleeve. .[.5. An end plug according to claim 3,where the said second flange is recessed within the sleeve..]. .[.6. Anend plug in accordance with claim 4 wherein said sleeve tapers at anangle of up to 10° off the vertical parallel to the internal surface ofthe sleeve for its entire length and said taper is at an angle of up to10° off the vertical with respect to the back flange in the direction ofthe symmetrical axis, containing in addition an inner sleeve parallel tosaid sleeve and perpendicular to the said second flange attachedcontinually to said second flange at the point of intersection of saidsecond flange and inner sleeve..].
 7. An end plug according to claim 1,wherein the intersection of surfaces comprising the sleeve and backflange meet in a concave radius and the intersection of the surfaces ofthe sleeve and .Iadd.the .Iaddend.second flange meet in a convex radius.8. An end plug according to claim 3, wherein the intersection ofsurfaces comprising the sleeve and back flange meets in a concave radiusand the intersection of the surface of the sleeve .[.in.]. .Iadd.and.Iaddend.the second flange meet in a convex radius. .[.9. An end plug inaccordance with claim 1 wherein said sleeve for a portion of its entirelength tapers at an angle up to 10° off the vertical with respect to theback flange and is concentric around the central axis of said plug and,in addition, said second flange is recessed within the sleeve..]. .[.10.An end plug in accordance with claim 9 wherein, the entire area of thesecond flange is perpendicular to said sleeve..].
 11. An end plug inaccordance with claim 1 wherein, in addition there is an inner sleeveparallel to said .Iadd.first .Iaddend.sleeve and perpendicular to saidsecond flange attached continually to said second flange at the point ofintersection of said second flange and the said inner sleeve. .[.12. Anend plug in accordance with claim 10 wherein in addition there is aninner sleeve parallel to said sleeve and perpendicular to said secondflange attached continually to said second flange at the point ofintersection of said second flange and inner sleeve..]. .[.13. An endplug according to claim 1 wherein the second flange is recessed withinthe sleeve and said second flange for its entire area is perpendicularto said sleeve..]. .[.14. An end plug according to claim 1 wherein thesecond flange is recessed within the sleeve, wherein the entire area ofsaid second flange is perpendicular to said sleeve, and an inner sleeveparallel to said sleeve and perpendicular to said second flange,attached continually to said second flange at the point of intersectionof said second flange and said inner sleeve..].